New Holland ENG 3178 – Engine Control Module (ECM / EDC): Timeout of CAN Message BC2EDC1

This fault indicates a communication error on the machine's Controller Area Network (CAN) bus. Specifically, the Engine Control Unit has timed out while waiting to receive the "BC2EDC1" message from the Body Computer (BC) or Vehicle Control Module (VCM).

• New Holland T7 and T8.xxx Series Tractors
• New Holland / Case Wheel Loaders (e.g., 721F, 821F, 921F)

1. 1

   Verify Body Computer (BC) voltage supply and check for a blown fuse that would prevent it from broadcasting.

2. 2

   Inspect the physical CAN bus harness connecting the Body Computer to the Engine ECU for short circuits, open circuits, or disconnected plugs.

3. 3

   With the battery disconnected, measure the resistance across the CAN High and CAN Low pins (should read approximately 60 ohms; 120 ohms indicates a broken wire/missing resistor, 0 ohms indicates a short).

4. 4

   Check for accompanying CAN timeout codes (like 3179, 3180, or 3096) which indicate a total bus failure rather than a single module failure.

1. 1

   Disconnect Power

   Turn off the machine and disconnect the battery ground to ensure safety while testing the wiring harness.

2. 2

   Harness Repair

   If the diagnostic checks reveal a broken wire, short to ground, or short to battery in the CAN lines between the BC and the EDC, locate the damaged section of the harness. Splice and seal the wiring using OEM-approved environmental splices, or replace the affected harness section.

3. 3

   Clean Connectors

   Disconnect the harness at both the Engine ECU and the Body Computer. Inspect the pins for corrosion, pushed-back pins, or moisture. Clean with contact cleaner and apply dielectric grease before reconnecting.

4. 4

   Module Replacement (If Necessary)

   If the wiring, terminating resistors, and power/ground supplies to the Body Computer are all perfectly intact, the CAN controller inside either the Body Computer or the Engine ECU has failed. Replace the defective module.

5. 5

   Clear Codes and Test

   Reconnect the battery, turn the key to the ON position, and use the New Holland Electronic Service Tool (EST) to clear the inactive fault codes. Start the engine and verify that the CAN communication is restored and the code does not return.